COVER INFORMATION Station: HART (Code Hh ) Experiment: Resolving the mystery of large VLBI-Gaia offsets Exp. Code: ek046a Schedule Version: 1.00 Processed by SCHED version: 11.50 Development version 11.5. Started Apr. 2 PI: Yuri Kovalev Address: Lebedev Physical Institute Profsoyuznaya 84/32 Moscow 117997 Russia Phone: +7 (495) 3332167 EMAIL: yyk@asc.rssi.ru Fax: +7 (495) 3332378 Phone during observation: +7 (915) 1546281 Observing mode: continuum Notes: Schedule for HART (Code Hh ) Page 2 Resolving the mystery of large VLBI-Gaia offsets UP: D => Below limits; H => Below horizon mask; W => still slewing at end; blank => Up. Early: Seconds between end of slew and start. Dwell: On source seconds. Disk: GBytes recorded to this point. TPStart: Recording start time. Frequencies are LO sum (band edge). SYNC: Time correlator is expected to sync up. ---------------------------------------------------------------------------------------- Start UT Source Start / Stop Early Disk TPStart Stop UT LST EL AZ HA UP ParA Dwell GBytes SYNC ---------------------------------------------------------------------------------------- --- Fri 18 Oct 2019 Day 291 --- Next scan frequencies: 22139.49 22139.49 22139.49 22139.49 22203.49 22203.49 22203.49 22203.49 22267.49 22267.49 22267.49 22267.49 22331.49 22331.49 22331.49 22331.49 Next BBC frequencies: 139.49 139.49 139.49 139.49 203.49 203.49 203.49 203.49 267.49 267.49 267.49 267.49 331.49 331.49 331.49 331.49 Next scan bandwidths: 32.00 32.00 32.00 32.00 32.00 32.00 32.00 32.00 32.00 32.00 32.00 32.00 32.00 32.00 32.00 32.00 01 30 51 J0741+3112 05 06 38 21.9 35.4 -2.6 0.0 0 0 01 30 51 01 34 06 =0738+313 05 09 54 22.3 34.8 -2.5 0.0 195 50 01 30 52 01 34 39 J0745+3142 05 10 27 21.4 35.2 -2.6 0.0 5 50 01 34 39 01 37 54 =0742+318 05 13 43 21.8 34.6 -2.6 0.0 195 100 01 34 40 01 38 58 J0815+3635 05 14 47 14.3 36.2 -3.0 0.0 22 100 01 38 58 01 42 13 =0812+367 05 18 02 14.7 35.7 -3.0 0.0 195 151 01 38 59 01 53 19 J0839+1802 05 29 10 26.1 51.7 -3.2 0.0 602 151 01 53 19 01 56 34 =0836+182 05 32 25 26.6 51.2 -3.1 0.0 195 201 01 53 20 01 57 04 J0842+1835 05 32 55 25.9 51.1 -3.2 0.0 4 201 01 57 04 02 00 19 =0839+187 05 36 11 26.5 50.5 -3.1 0.0 195 251 01 57 05 02 01 38 J0940+2603 05 37 30 11.6 53.4 -4.1 0.0 23 251 02 01 38 02 04 53 =0937+262 05 40 45 12.2 52.9 -4.0 0.0 195 301 02 01 39 03 53 39 J0741+3112 07 29 49 32.9 3.2 -0.2 0.0 6438 301 03 53 39 03 56 54 =0738+313 07 33 05 32.9 2.4 -0.2 0.0 195 352 03 53 40 03 57 32 J0745+3142 07 33 44 32.4 3.3 -0.2 0.0 11 352 03 57 32 04 00 47 =0742+318 07 36 59 32.4 2.5 -0.2 0.0 195 402 03 57 33 04 02 09 J0815+3635 07 38 21 26.9 8.6 -0.6 0.0 40 402 04 02 09 04 05 24 =0812+367 07 41 36 27.0 7.9 -0.6 0.0 195 452 04 02 10 04 07 04 J0839+1802 07 43 17 44.0 19.1 -1.0 0.0 36 452 04 07 04 04 10 19 =0836+182 07 46 32 44.2 18.1 -0.9 0.0 195 502 04 07 05 04 10 51 J0842+1835 07 47 04 43.5 18.5 -0.9 0.0 6 502 04 10 51 04 14 06 =0839+187 07 50 20 43.8 17.5 -0.9 0.0 195 553 04 10 52 04 15 38 J0940+2603 07 51 52 31.8 29.1 -1.8 0.0 36 553 04 15 38 04 18 53 =0937+262 07 55 08 32.2 28.3 -1.8 0.0 195 603 04 15 39 04 20 30 J1023+3948 07 56 45 15.9 28.7 -2.5 0.0 42 603 04 20 30 04 23 45 =1020+400 08 00 00 16.3 28.2 -2.4 0.0 195 653 04 20 31 Schedule for HART (Code Hh ) Page 3 Resolving the mystery of large VLBI-Gaia offsets UP: D => Below limits; H => Below horizon mask; W => still slewing at end; blank => Up. Early: Seconds between end of slew and start. Dwell: On source seconds. Disk: GBytes recorded to this point. TPStart: Recording start time. Frequencies are LO sum (band edge). SYNC: Time correlator is expected to sync up. ---------------------------------------------------------------------------------------- Start UT Source Start / Stop Early Disk TPStart Stop UT LST EL AZ HA UP ParA Dwell GBytes SYNC ---------------------------------------------------------------------------------------- --- Fri 18 Oct 2019 Day 291 --- 04 35 04 J1159+2914 08 11 21 12.2 48.8 -3.8 0.0 605 653 04 35 04 04 38 19 =1156+295 08 14 37 12.8 48.3 -3.8 0.0 195 703 04 35 05 06 31 51 J0741+3112 10 08 27 23.1 326.4 2.4 0.0 6654 703 06 31 51 06 35 06 =0738+313 10 11 43 22.7 325.8 2.5 0.0 195 754 06 31 52 06 35 40 J0745+3142 10 12 17 22.8 326.8 2.4 0.0 6 754 06 35 40 06 38 55 =0742+318 10 15 32 22.4 326.2 2.5 0.0 195 804 06 35 41 06 40 06 J0815+3635 10 16 44 21.5 334.4 2.0 0.0 30 804 06 40 06 06 43 21 =0812+367 10 20 00 21.2 333.8 2.1 0.0 195 854 06 40 07 06 49 07 J0839+1802 10 25 47 39.2 327.1 1.8 0.0 282 854 06 49 07 06 52 22 =0836+182 10 29 02 38.8 326.2 1.8 0.0 195 904 06 49 08 06 52 52 J0842+1835 10 29 32 38.6 327.1 1.8 0.0 4 904 06 52 52 06 56 07 =0839+187 10 32 48 38.2 326.3 1.8 0.0 195 955 06 52 53 06 57 53 J0940+2603 10 34 34 36.6 345.1 0.9 0.0 50 955 06 57 53 07 01 08 =0937+262 10 37 50 36.4 344.2 0.9 0.0 195 1005 06 57 54 07 03 23 J1023+3948 10 40 05 24.3 356.7 0.3 0.0 80 1005 07 03 23 07 06 38 =1020+400 10 43 20 24.3 356.0 0.3 0.0 195 1055 07 03 24 07 12 37 J1159+2914 10 49 20 32.4 18.4 -1.2 0.0 284 1055 07 12 37 07 15 52 =1156+295 10 52 35 32.6 17.6 -1.1 0.0 195 1105 07 12 38 07 17 24 J1331+3030 10 54 08 22.2 36.3 -2.6 0.0 20 1105 07 17 24 07 20 39 =1328+307 10 57 23 22.6 35.7 -2.6 0.0 195 1156 07 17 25 07 21 37 J1407+2827 10 58 21 19.2 43.3 -3.2 0.0 13 1156 07 21 37 07 24 52 =1404+286 11 01 37 19.7 42.7 -3.1 0.0 195 1206 07 21 38 09 26 37 J0839+1802 13 03 42 12.5 297.3 4.4 0.0 7112 1206 09 26 37 09 29 52 =0836+182 13 06 57 11.8 296.9 4.4 0.0 195 1256 09 26 38 09 30 21 J0842+1835 13 07 26 12.0 297.6 4.4 0.0 3 1256 09 30 21 09 33 36 =0839+187 13 10 42 11.3 297.2 4.5 0.0 195 1306 09 30 22 09 35 01 J0940+2603 13 12 08 17.4 311.5 3.5 0.0 30 1306 09 35 01 09 38 16 =0937+262 13 15 23 16.8 311.0 3.6 0.0 195 1356 09 35 02 09 39 50 J1023+3948 13 16 58 13.1 327.3 2.9 0.0 40 1356 09 39 50 09 43 05 =1020+400 13 20 13 12.7 326.8 2.9 0.0 195 1407 09 39 51 Schedule for HART (Code Hh ) Page 4 Resolving the mystery of large VLBI-Gaia offsets UP: D => Below limits; H => Below horizon mask; W => still slewing at end; blank => Up. Early: Seconds between end of slew and start. Dwell: On source seconds. Disk: GBytes recorded to this point. TPStart: Recording start time. Frequencies are LO sum (band edge). SYNC: Time correlator is expected to sync up. ---------------------------------------------------------------------------------------- Start UT Source Start / Stop Early Disk TPStart Stop UT LST EL AZ HA UP ParA Dwell GBytes SYNC ---------------------------------------------------------------------------------------- --- Fri 18 Oct 2019 Day 291 --- 09 46 28 J1159+2914 13 23 37 31.5 338.7 1.4 0.0 128 1407 09 46 28 09 49 43 =1156+295 13 26 52 31.2 337.9 1.4 0.0 195 1457 09 46 29 09 52 19 J1331+3030 13 29 28 33.7 0.7 -0.0 0.0 83 1457 09 52 19 09 55 34 =1328+307 13 32 44 33.7 359.8 0.0 0.0 195 1507 09 52 20 09 56 39 J1407+2827 13 33 49 35.1 9.2 -0.6 0.0 20 1507 09 56 39 09 59 54 =1404+286 13 37 05 35.2 8.3 -0.5 0.0 195 1557 09 56 40 SETUP FILE INFORMATION: NOTE: If DOPPLER, FREQ, or BW were used, see the individual scans for the final BBC settings. ======== Setup file: sess319.K2048 --- WARNING --- This group does not match an entry in the frequency catalog. This might be ok because the catalog is not complete. But be very careful to be sure that the setup is correct. Setup group: 7 Station: HART Total bit rate: 2048 Format: VDIF Bits per sample: 2 Sample rate: 64.000 Number of channels: 16 DBE type: DBBC_DDC Speedup factor: 1.00 Disk used to record data. 1st LO= 22000.00 22000.00 22000.00 22000.00 22000.00 22000.00 22000.00 22000.00 22000.00 22000.00 22000.00 22000.00 22000.00 22000.00 22000.00 22000.00 Net SB= L L U U L L U U L L U U L L U U IF SB = U U U U U U U U U U U U U U U U Pol. = RCP LCP RCP LCP RCP LCP RCP LCP RCP LCP RCP LCP RCP LCP RCP LCP BBC = 1 9 1 9 2 10 2 10 3 11 3 11 4 12 4 12 BBC SB= L L U U L L U U L L U U L L U U IF = A1 C1 A1 C1 A1 C1 A1 C1 A1 C1 A1 C1 A1 C1 A1 C1 The following frequency sets based on these setups were used. Frequency Set: 17 Setup file default. Used with PCAL = off LO sum= 22139.49 22139.49 22139.49 22139.49 22203.49 22203.49 22203.49 22203.49 22267.49 22267.49 22267.49 22267.49 22331.49 22331.49 22331.49 22331.49 BBC fr= 139.49 139.49 139.49 139.49 203.49 203.49 203.49 203.49 267.49 267.49 267.49 267.49 331.49 331.49 331.49 331.49 Bandwd= 32.00 32.00 32.00 32.00 32.00 32.00 32.00 32.00 32.00 32.00 32.00 32.00 32.00 32.00 32.00 32.00 Matching frequency sets: 17 Track assignments are: track1= 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 barrel=roll_off POSITIONS OF SOURCES USED IN RECORDING SCANS Source Source position (RA/Dec) Error (B1950) (J2000) (Date) (mas) 0149+710 01 49 20.806509 * 01 53 25.851060 01 55 06.521491 0.52 * J0153+7115 71 00 20.67761 * 71 15 06.46340 71 20 49.56135 0.14 /home/guest/rmc/SCHED/sched11.5/catalogs/rfc_2018a_cat.key rfc_2018a Petrov and Kovalev, in preparation 185 observations 0738+313 07 38 00.178552 * 07 41 10.703301 07 42 24.639726 0.12 * J0741+3112 31 19 02.05890 * 31 12 00.22889 31 09 07.91277 0.10 /home/guest/rmc/SCHED/sched11.5/catalogs/rfc_2018a_cat.key rfc_2018a Petrov and Kovalev, in preparation 11407 observations 0742+318 07 42 30.742935 * 07 45 41.671441 07 46 55.727458 0.18 * J0745+3142 31 50 16.25936 * 31 42 56.61744 31 39 57.23294 0.18 /home/guest/rmc/SCHED/sched11.5/catalogs/rfc_2018a_cat.key rfc_2018a Petrov and Kovalev, in preparation 111 observations 0812+367 08 12 10.710945 * 08 15 25.944864 08 16 41.402208 0.13 * J0815+3635 36 44 27.45312 * 36 35 15.14877 36 31 30.64160 0.10 /home/guest/rmc/SCHED/sched11.5/catalogs/rfc_2018a_cat.key rfc_2018a Petrov and Kovalev, in preparation 4342 observations 0820+560 08 20 53.203690 * 08 24 47.236366 08 26 17.316424 0.18 * J0824+5552 56 02 27.45540 * 55 52 42.66931 55 48 38.93144 0.10 /home/guest/rmc/SCHED/sched11.5/catalogs/rfc_2018a_cat.key rfc_2018a Petrov and Kovalev, in preparation 5477 observations 0836+182 08 36 40.098254 * 08 39 30.721374 08 40 36.601725 0.13 * J0839+1802 18 13 24.80253 * 18 02 47.14256 17 58 36.84550 0.16 /home/guest/rmc/SCHED/sched11.5/catalogs/rfc_2018a_cat.key rfc_2018a Petrov and Kovalev, in preparation 716 observations 0839+187 08 39 14.084300 * 08 42 05.094176 08 43 11.105293 0.11 * J0842+1835 18 46 27.27510 * 18 35 40.99057 18 31 27.19551 0.11 /home/guest/rmc/SCHED/sched11.5/catalogs/rfc_2018a_cat.key rfc_2018a Petrov and Kovalev, in preparation 2039 observations 0850+581 08 50 50.156150 * 08 54 41.996414 08 56 10.782857 0.20 * J0854+5757 58 08 55.67772 * 57 57 29.93906 57 52 47.39577 0.11 /home/guest/rmc/SCHED/sched11.5/catalogs/rfc_2018a_cat.key rfc_2018a Petrov and Kovalev, in preparation 1344 observations 0937+262 09 37 22.003670 * 09 40 14.722784 09 41 20.979544 0.16 * J0940+2603 26 17 07.70830 * 26 03 29.94570 25 58 08.56497 0.25 /home/guest/rmc/SCHED/sched11.5/catalogs/rfc_2018a_cat.key rfc_2018a Petrov and Kovalev, in preparation 65 observations 1003+830 10 03 25.755735 * 10 10 15.783048 10 12 42.350074 1.25 * J1010+8250 83 04 56.60730 * 82 50 14.38373 82 44 12.64387 0.14 /home/guest/rmc/SCHED/sched11.5/catalogs/rfc_2018a_cat.key rfc_2018a Petrov and Kovalev, in preparation 190 observations 1020+400 10 20 14.564689 * 10 23 11.565665 10 24 18.985480 0.13 * J1023+3948 40 03 26.57363 * 39 48 15.38532 39 42 15.36293 0.11 /home/guest/rmc/SCHED/sched11.5/catalogs/rfc_2018a_cat.key rfc_2018a Petrov and Kovalev, in preparation 1594 observations 1124+455 11 24 13.766459 * 11 26 57.654951 11 27 59.506244 0.19 * J1126+4516 45 32 36.89523 * 45 16 06.28414 45 09 37.99194 0.17 /home/guest/rmc/SCHED/sched11.5/catalogs/rfc_2018a_cat.key rfc_2018a Petrov and Kovalev, in preparation 169 observations 1146+531 11 46 18.019057 * 11 48 56.569084 11 49 55.910598 0.24 * J1148+5254 53 11 05.71063 * 52 54 25.32289 52 47 53.20692 0.14 /home/guest/rmc/SCHED/sched11.5/catalogs/rfc_2018a_cat.key rfc_2018a Petrov and Kovalev, in preparation 159 observations 1156+295 11 56 57.786210 * 11 59 31.833911 12 00 30.210242 0.11 * J1159+2914 29 31 25.73872 * 29 14 43.82682 29 08 16.68020 0.10 /home/guest/rmc/SCHED/sched11.5/catalogs/rfc_2018a_cat.key rfc_2018a Petrov and Kovalev, in preparation 93824 observations 1214+588 12 14 44.916752 * 12 17 11.018812 12 18 05.067190 0.38 * J1217+5835 58 52 05.64160 * 58 35 26.24606 58 28 55.73044 0.20 /home/guest/rmc/SCHED/sched11.5/catalogs/rfc_2018a_cat.key rfc_2018a Petrov and Kovalev, in preparation 190 observations 1231+481 12 31 50.237054 * 12 34 13.330775 12 35 06.828646 0.19 * J1234+4753 48 10 22.70476 * 47 53 51.23617 47 47 27.04946 0.15 /home/guest/rmc/SCHED/sched11.5/catalogs/rfc_2018a_cat.key rfc_2018a Petrov and Kovalev, in preparation 395 observations 1328+307 13 28 49.657783 * 13 31 08.288075 13 32 00.554312 0.18 * J1331+3030 30 45 58.64055 * 30 30 32.95919 30 24 40.56399 0.17 /home/guest/rmc/SCHED/sched11.5/catalogs/rfc_2018a_cat.key rfc_2018a Petrov and Kovalev, in preparation 603 observations 1333+459 13 33 15.707444 * 13 35 21.962227 13 36 08.999531 0.20 * J1335+4542 45 57 56.43914 * 45 42 38.23211 45 36 47.44089 0.13 /home/guest/rmc/SCHED/sched11.5/catalogs/rfc_2018a_cat.key rfc_2018a Petrov and Kovalev, in preparation 136 observations 1404+286 14 04 45.615157 * 14 07 00.394415 14 07 51.228448 0.11 * J1407+2827 28 41 29.23512 * 28 27 14.69015 28 21 52.09474 0.10 /home/guest/rmc/SCHED/sched11.5/catalogs/rfc_2018a_cat.key rfc_2018a Petrov and Kovalev, in preparation 72228 observations 1435+638 14 35 37.240605 * 14 36 45.802154 14 37 09.538364 0.23 * J1436+6336 63 49 35.85998 * 63 36 37.86631 63 31 44.22936 0.10 /home/guest/rmc/SCHED/sched11.5/catalogs/rfc_2018a_cat.key rfc_2018a Petrov and Kovalev, in preparation 1906 observations 1623+578 16 23 27.706688 * 16 24 24.807567 16 24 45.120182 0.19 * J1624+5741 57 48 03.95393 * 57 41 16.28097 57 38 54.44136 0.10 /home/guest/rmc/SCHED/sched11.5/catalogs/rfc_2018a_cat.key rfc_2018a Petrov and Kovalev, in preparation 6591 observations 1637+574 16 37 17.425181 * 16 38 13.456296 16 38 33.466026 0.19 * J1638+5720 57 26 15.76131 * 57 20 23.97902 57 18 24.63714 0.10 /home/guest/rmc/SCHED/sched11.5/catalogs/rfc_2018a_cat.key rfc_2018a Petrov and Kovalev, in preparation 11099 observations 1656+477 16 56 39.600756 * 16 58 02.779585 16 58 33.789412 0.15 * J1658+4737 47 42 19.63006 * 47 37 49.23077 47 36 22.63801 0.10 /home/guest/rmc/SCHED/sched11.5/catalogs/rfc_2018a_cat.key rfc_2018a Petrov and Kovalev, in preparation 1396 observations 1928+738 19 28 49.350194 * 19 27 48.495147 19 27 24.020296 0.37 * J1927+7358 73 51 44.92748 * 73 58 01.56992 74 00 48.66910 0.10 /home/guest/rmc/SCHED/sched11.5/catalogs/rfc_2018a_cat.key rfc_2018a Petrov and Kovalev, in preparation 7201 observations 2030+547 20 30 29.095869 * 20 31 47.958535 20 32 19.059799 0.18 * J2031+5455 54 44 49.23056 * 54 55 03.13949 54 59 23.84183 0.11 /home/guest/rmc/SCHED/sched11.5/catalogs/rfc_2018a_cat.key rfc_2018a Petrov and Kovalev, in preparation 1783 observations SOURCE SCAN SUMMARY FOR SOURCES LISTED ABOVE Scan hours are for recording scans only. Baseline hours are only counted for scans above horizon at both ends. Source Setup file Frequency sets Observing hours (duplicates not shown) Scan Baseline J0153+7115 sess319.K2048 1 2 3 4 5 6 7 8 9 13 14 0.272 32.600 J0741+3112 sess319.K2048 1 2 3 4 5 6 7 8 9 13 14 17 0.272 27.993 J0745+3142 sess319.K2048 1 2 3 4 5 6 7 8 9 13 14 17 0.272 27.995 J0815+3635 sess319.K2048 1 2 3 4 5 6 7 8 9 13 14 17 0.272 27.129 J0824+5552 sess319.K2048 1 2 3 4 5 6 7 8 9 13 14 0.272 29.404 J0839+1802 sess319.K2048 1 2 3 4 5 6 7 8 9 13 14 17 0.272 25.577 J0842+1835 sess319.K2048 1 2 3 4 5 6 7 8 9 13 14 17 0.272 25.577 J0854+5757 sess319.K2048 1 2 3 4 5 6 7 8 9 13 14 0.272 30.162 J0940+2603 sess319.K2048 1 2 3 4 5 6 7 8 9 13 14 17 0.272 25.565 J1010+8250 sess319.K2048 1 2 3 4 5 6 7 8 9 13 14 0.272 32.600 J1023+3948 sess319.K2048 1 2 3 4 5 6 7 8 9 13 14 17 0.272 29.748 J1126+4516 sess319.K2048 1 2 3 4 5 6 7 8 9 13 14 0.272 26.641 J1148+5254 sess319.K2048 1 2 3 4 5 6 7 8 9 13 14 0.272 29.380 J1159+2914 sess319.K2048 1 2 3 4 5 6 7 8 9 13 14 17 0.272 24.073 J1217+5835 sess319.K2048 1 2 3 4 5 6 7 8 9 13 14 0.272 30.975 J1234+4753 sess319.K2048 1 2 3 4 5 6 7 8 9 13 14 0.272 25.125 J1331+3030 sess319.K2048 1 2 3 4 5 6 7 8 9 13 14 17 0.272 24.225 J1335+4542 sess319.K2048 1 2 3 4 5 6 7 8 9 13 14 0.272 23.662 J1407+2827 sess319.K2048 1 2 3 4 5 6 7 8 9 13 14 17 0.272 22.004 J1436+6336 sess319.K2048 1 2 3 4 5 6 7 8 9 13 14 0.272 32.600 J1624+5741 sess319.K2048 1 2 3 4 5 6 7 8 9 13 14 0.272 31.787 J1638+5720 sess319.K2048 1 2 3 4 5 6 7 8 9 13 14 0.272 31.787 J1658+4737 sess319.K2048 1 2 3 4 5 6 7 8 9 13 14 0.272 22.155 J1927+7358 sess319.K2048 1 2 3 4 5 6 7 8 9 13 14 0.272 32.600 J2031+5455 sess319.K2048 1 2 3 4 5 6 7 8 9 13 14 0.272 26.434 EFFECT OF SOLAR CORONA The solar corona can cause unstable phases for sources too close to the Sun. SCHED provides warnings at individual scans for distances less than 10 degrees. The distance from the Sun to each source in this schedule is: Source Sun distance (deg) J0153+7115 118.0 J0741+3112 92.4 J0745+3142 91.6 J0815+3635 86.6 J0824+5552 90.2 J0839+1802 76.7 J0842+1835 76.2 J0854+5757 87.1 J0940+2603 66.0 J1010+8250 94.7 J1023+3948 65.4 J1126+4516 61.2 J1148+5254 65.9 J1159+2914 44.3 J1217+5835 69.6 J1234+4753 58.6 J1331+3030 39.9 J1335+4542 55.1 J1407+2827 38.9 J1436+6336 74.1 J1624+5741 75.9 J1638+5720 77.0 J1658+4737 73.3 J1927+7358 98.9 J2031+5455 106.6 Barry Clark estimates from predictions by Ketan Desai of IPM scattering sizes that the Sun will cause amplitude reductions on the longest VLBA baselines at a solar distance of 60deg F^(-0.6) where F is in GHz. For common VLBI bands, this is: 327 MHz 117. deg 610 MHz 81. deg 1.6 GHz 45. deg 2.3 GHz 36. deg 5.0 GHz 23. deg 8.4 GHz 17. deg 15.0 GHz 12. deg 22.0 GHz 9. deg 43.0 GHz 6. deg